Emission Performance of Scandate Cathodes Prepared by Pulse Laser Deposition

In order to improve the emission performance of cathodes to meet the demands of new type devices, this paper develops a new-type scandate cathode coated with W+BaO-Sc2O3-SrO film prepared by Pulse Laser Deposition (PLD) technology. The experiment obtains emission current characteristics measured as a function of voltage and temperature and analyzes the emission mechanism. The test results indicate that at 1100C the current density of the new cathode reaches 305.5 A/cm2; and the layer of Ba-Sc-Sr-O is the key to this excellent performance. The abnormal Schottky effect that the cathode appears is also investigated by using semiconductor model.